It is important that you get as many touches with a volleyball as possible on a daily basis. If you do not have one, you can order one online from Walmart, Amazon, etc.
Here are some drills you can do on your own at home:
Each week add 5-10 reps to each workout. If it is a timed workout, then add 10-15 seconds to make it longer. If you are not familiar with the workout moves, then look it up on YouTube. It should be easy to find. Also, make sure you add some ball control drills into each day’s workout. Pick a skill to focus on each day, or mix it up! Getting 15-20 minutes of touches each day will help tremendously.